An increasing number of deployed radio access networks are based on different radio access technologies (RATs). The availability of multiple access alternatives offers the flexibility of using different RATs and the capability of increasing the overall transmission capacity, providing better service quality, and reducing the deployment costs for wireless access. In the future, a mixture of heterogeneous radio technologies may be available. Presently, mobile terminals have the capability for versatile usage of radio communication resources, such as Extended GSM (Global System for Mobile communications) (EGSM), High Speed Packet Access (HSPA), Wireless Local Area Network (WEAN), BlueTooth (BT), and the like. Some considerations involve utilizing several access techniques simultaneously.
Multi-radio access technologies have been given substantial attention recently. A modern base station platform can expand its supported technologies to cover GSM/Enhanced Data Rates for GSM Evolution (EDGE), wideband code division multiple access (WCDMA)/high speed packet access (HSPA) and long term evolution (LTE), all running concurrently in a single unit. Base stations may support a multi-radio access technology in order to meet the needs of new and existing 2nd generation and 3rd generation operators, who can use their existing infrastructure to deploy new network-wide technologies via simple software upgrades to 3rd generation or LTE.